"Wow," that's probably the least useful reply yet. I'd let it go, but after your criticism of the earlier posts, I'll try to constructively criticize yours:
1. Map datum. If he is consistently getting within 20 - 30 feet of a cache, I'd say he is using the correct datum. An incorrect datum would likely cause an error in the hundreds of feet.
2. Read manual - tell GPS what area of world you are in. This is helpful when using a gpsr for the first time or in a new geographical area to help it lock on quicker. If he has already got satellite lock indicating 20 - 30 foot accuracy, this would not be helpful or necessary.
3. WAAS. Not using WAAS is not going to throw your accuracy off by an additional 20 - 30 feet. At best, a good WAAS signal might improve your accuracy by 5 - 10 feet. And as far as picking up at least one WAAS satellite, I think picking up one is most you could hope for. Anyone ever get 2 WAAS signals at the same time?
Well - not ment to criticize anyone, but here it is from Magellen:
1) The reason for initialization is to speed up the process for computing the
first position fix when the SporTrak has no last position computed in
memory (i.e.,when the SporTrak is brand new or memory has been
cleared).This gives the SporTrak an approximate indication of where it is
located so it can use its satellite almanac (stored in permanent memory)to
estimate what satellites are overhead and which ones it should be looking
for.
2) Position coordinates on your receiver do not match the location on your map.
1.Make sure that your receiver is set up to use the same datum as your map.
The map datum is generally shown in the map legend.See Setup -
Changing the Map Datum under Reference for instructions on selecting the
map datum in your receiver.
2.Check your LAT/LON format.Make sure that the format selected in
COORDINATE SYSTEM (DEG/MIN/SEC or DEG/MIN.MM)is in
the same format as the map you are using.
3) How accurate will my GPS receiver be with WAAS?The FAA reports that
expected accuracy can be improved to around 7 meters vertically and horizon-
tally.Our own testing suggests that Magellan GPS receivers will typically
experience accuracy improvements to around 3 meters.You can expect to see this
level of accuracy for 95%of the time that you are receiving WAAS signals.
So - like I said.... check your map datum, check for WAAS signal, and read the book.
Or - don't listen to me because i'm just a Mr. Know-it-all anyway.